Jens Spahn, the deputy finance minister, according to commentators is believed to be Germany chancellor-in-waiting after a wave of dissatisfaction for Mrs Merkel, who has held the role for 11 years.
“The whole Schengen treaty and the situation you have with freedom of movement throughout continental Europe can only work if we are able and willing to secure our borders,” he said.
Jens Spahn ripped into the EU's 'catastrophic' Schengen policy
Free movement throughout continental Europe can only work if we are able to secure our borders
“Obviously we were not able to secure the Aegean Sea and the Mediterranean Sea. There we are getting better.
“We have to regain control and have regained a lot of control already, but not yet everything that needs to be done.”
The German declared it was a “debate that needs to be done”, he added: “If something like that is happening in the past two years with the migrants coming into Europe, then it is quite normal that you have a controversial debate in society and in a party.
“I just see a controversial debate in a party. If you do it the right way and with good argument – that is what we did in the Christian Democratic Union.”
Mr Spahn added his European colleagues should work together to find a continent-wide solution to the problem, with many citizens concerned after a rise in terrorist activity during the migrant crisis.
He cited the failings of Schengen for the Berlin terror attack after suspect Anis Amri was allowed to travel freely across Europe to carry out the attack after serving several prison sentences.
“We have not had a situation like this before in Germany or the European Union. Now, it is about regaining control and discussing security issues,” he said.
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“Of course, fighting terrorism, and we have had terror attacks before this refugee influx – but it’s about screening people that are coming into the European Union. By the way, the terrorist of Berlin was actually let out of a Greek prison too early.
Migrants clash with police across Europe Wed, February 15, 2017
Migrants clash with each other in over crowded camps across Europe.
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Moroccan Police look at immigrants trying to jump the six-meter-high fence in Ceuta, Spanish enclave on the north of Africa, 09 December 2016.
“We have to find a European solution and I find it quite normal that you have controversial debates in a society and in an upcoming campaign because it is not an average issue. It is a fundamental question of society and Europe.”
Under fire has signalled a readiness to discuss the parameters of free movement of people in the EU, suggesting Brexit negotiations may introduce some room for manoeuvre.
While not openly calling for a German vote to leave the EU, Mr Spahn has claimed: “The debate we should be having in Germany, too: does Germany want to be part of a European Union that a majority of Brits feel belongs to them?”
He called on all of the European partners in the Brexit negotiations to aim for a smooth transition when Britain leaves the bloc, wanting them to “do everything we can for a ‘soft’ Brexit”.
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